Absolutely. I did 9 dogs back in the spring. As a result I did myself as well...my hair felt awful. It has to be food grade. The best way to apply it is to use one of those powdered sugar tins that have little holes in the top.

My dog didn't mind, the cat didn't like it the first time. Second time I just picked her up and did it more casual as I was petting her. The stuff that fell of I even laid her down in it and petted her some more. Now I just need some dry days so I can put it out in the yard. Pulled out the fridge and stove and swept and put down a thick layer, that ant problem should be gone in no time!

Some young kittens were dumped off at our house and they were crawling with fleas, but too young to use flea medication that is made for cats. I dusted them with DE and it helped a lot. They looked like they had ripped open a bag of flour for a while, but it does seem to have helped with the fleas and didn't seem to harm the kittens.

I would not use Diatomaceous Earth (DE) on my dogs or cat for several reasons: (1) my dogs come indoors sometimes & I wouldn't want SiO2 (quartz, Moh's hardness = 7) scratching my hardwood floors; (2) just as it would be harmful for me to breathe it (and I would wear a mask), so it would be harmful to my dogs' lungs; (3) IMHO, it is very minimally effective against fleas & no more so than the dog taking a good dust bath and (4) the stuff is costly.